The advent of cable television systems has made possible the transmission and availability of a wide array of television programs directly to the homes of subscribers, i.e., viewers. For a majority of viewers, there no longer exists a restriction to the number of VHF and UHF channels that are available in a particular geographic region. Rather, cable television systems have allowed for the delivery of hundreds of channels with the only major restriction being the transmission characteristics of the cable itself and the ability to compress the information in television programs into the narrower-bandwidth channels. The impact of cable television in the United States has been universal and in some ways, controversial.
More particularly, the significant increase in television programming content available in the United States has lead to certain controversy of how to regulate the viewing of programs containing varying amounts of violence, sexual content, and coarse language. In response to the general public's concerns, and in particular parents, the U.S. Congress passed the Telecommunications Act of 1996. The Telecommunications Act requires that all new television sets (13 inches or larger) made available in the U.S. be equipped with the so-called "V-chip", a device that allows parents to block television programming in three areas: violence, sex, and language. The technology for implementing the V-chip is similar to that used in delivering the current closed-captioning features of modern day programming. That is, program rating information is transmitted along with the television signal, and be decoded by the V-chip within the television set. The V-chip compares the rating code carried by the program with values preset by the viewer. This allows the V-chip to block entire classes of programs which carry rating codes higher than the preset viewer values.
Pursuant to a recommendation in the Telecommunications Act, and on a voluntary basis, the television broadcast industry developed an age-based rating plan which provides four main program designations (so-called "TV Parental Guidelines"): TV-G (general audiences), TV-PG (parental guidance suggested), TV-14 (parents strongly cautioned), and TV-M (mature audiences only.) In modern-day broadcasts, the TV Parental Guidelines appear at the beginning of each televised program, except for news and sports programs which are exempt from the Act. Thus, the implementation of the V-chip is directed at assisting parents in controlling their children's access to television programming that they believe contains inappropriate or potentially harmful content. Essentially, parents may block an entire category of programs, e.g., TV-M, from being viewed by their children.
In addition to the V-chip, there exist other commercially available devices which allow parents to regulate their children's television viewing habits. For example, SuperVision.TM., available from SuperVision, Inc., La Quintas, Calif., is marketed as a V-chip alternative which allows parents to automatically regulate the amount of television their children view. The device attaches to a television and is programmed by the user to provide, e.g., specific allotted times during any given week when a child can watch television. Similar to the V-chip, this device effectively blocks access to an entire class of programming.
While the above-described devices are effective in regulating television viewing habits, they each share a characteristic which somewhat limits the flexibility of the subscriber in having total control of a their viewing choices, e.g., viewing by their children. That is, each of these devices block entire classes of programs from viewing but do not allow for the blocking of individual programs within a class. For example, the user can block all TV-PG programs from being viewed but cannot allow a particular TV-PG program to be viewed if they determine that this particular program's content is acceptable for viewing. Thus, the viewer is presented with an "all-or-nothing" approach for regulating their child's (and their own) viewing of television programming.
Therefore, a need exists for a signal blocking technique which allows for the blocking of individual programs and/or portions of programs within a particular class of programs while allowing for the viewing of certain other programs within the same programming class.